#2452: Add a flag to disable the implicit qualified import of every available
module in interactive mode
--------------------------------+-------------------------------------------
Reporter: jcpetruzza | Owner:
Type: feature request | Status: new
Priority: normal | Component: Compiler (Type checker)
Version: 6.9 | Severity: minor
Keywords: | Testcase:
Architecture: Unknown | Os: Unknown
--------------------------------+-------------------------------------------
In interactive mode every available module is implicitly imported
qualified. While this is very convenient when working with GHCi, it can be
a little annoying in other contexts.
For instance, in a lambdabot-like application, one would like to rely on
the type of a given expression to decide if it is side-effect free and,
thus, safe to execute. However, because every module in the `base` package
is imported qualified one has to do a manual check to filter out cases
like:
{{{
ghc -e 'System.IO.Unsafe.unsafePerformIO (evilStuff >> return "i'm an
innocent string")'
}}}
Another example would be a GHC-API based refactoring tool that wants to
check if a refactored expression typechecks before modifying the code. If
every module is imported qualified, the tool might get many false
positives.
The proposal is to keep the current behaviour as the default but to add a
`-fno-implicit-import-qualified` flag to disable it when needed. The
following should fail to execute:
{{{
ghc -fno-implicit-import-qualified -e 'System.IO.Unsafe.unsafePerformIO
(evilStuff >> return "i'm an innocent string")'
}}}
--
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2452>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler_______________________________________________
Glasgow-haskell-bugs mailing list
[email protected]
http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
